Pan musical instruments are a family of pitched percussion instruments originating from the island of Trinidad in the late 1930s. Pans may come in various voices/instruments representing, among others, soprano, alto, tenor, and bass. Each voice has a plurality of note facets shaped on the playing surface. The quantity of note facets may vary from one to thirty or more, depending on the range, diameter, and number of drums for any particular instrument.
Pans have traditionally been hand crafted from 55 gallon 22.5″ diameter industrial metal containers/barrels, and most pans currently made are still hand hammered from such containers/barrels. The top and bottom heads of such barrels ordinarily consist of 18 gauge steel of unspecified composition and hardness. These heads are shaped into a concave bowl using large hammers. With smaller hammers, note facets are then shaped based on a small number of rough measurements incorporating non-precise measuring techniques and devices. The skirt, or sidewall, for the pan is then cut from the barrel to the desired length. Skirt length varies depending on the desired register or voice of the pan (soprano, alto, tenor, or bass). The pan is then heat treated, cleaned, and prepared for tuning. The tuning process is performed using a series of small hammers, a strobe tuner, and many hours of focused concentration by a skilled craftsman. After tuning, the pan is painted or chrome plated in order to prevent corrosion. The instrument then undergoes a final tuning in a suspended position similar to its position when being played.
The traditional process outlined above generally requires many hours to create an instrument, and can take as many as one hundred eighty hours or more depending on the instrument voice and the skill of the craftsman. This lengthy process has made it difficult for the industry to meet the current market demand for such instruments. Further, such traditional pans and pan-making processes suffer several disadvantages.
First, one rate limiting step in the mass production of high quality pans has been the starting material, namely, the 55 gallon oil barrel. The type of material used to produce an industrial container, normally 18 gauge cold rolled steel of unspecified composition, hardness, and varying thickness, does not yield a consistent or high quality pan. The variation in the steel from barrel to barrel requires the craftsman to incorporate varying methods of building and tuning. This greatly increases the amount of time required to produce a pan instrument and sometimes is not physically possible to achieve success.
Second, the standard 22.5″ diameter industrial barrel presents several major problems and limitations. This diameter does not provide sufficient surface area for a complete layout of optimal size note facets, thereby requiring the craftsman to reduce the size of the note facets in an attempt to produce an instrument with a maximal tonal range. Unfortunately, shrinking the note facets compromises sound quality, requires longer tuning time, and results in far less stable notes. Stability as used herein refers to a combination of how well a note can reproduce its intended frequency when struck at varying velocities with a mallet, and how long the note will remain in tune. The inventors herein have discovered that larger note facet sizes produce cleaner and more stable frequencies on each note facet, and therefore, one aspect of the invention provides a larger diameter starting material which accommodates larger note facets. Expanding the size of the starting material has made it possible to increase the note sizes as well as the amounts of interstitial material surrounding each note facet, resulting in significantly better sounding notes while maintaining or exceeding the tonal pitch range of conventional pans.
Third, the manner in which the head is customarily attached to the sidewall or skirt, via crimping, creates additional problems found in most, if not all, instruments built from industrial containers. The rim formed by this crimping process tends to separate slightly during the initial hammering phase, i.e., the sinking and shaping of the bowl, causing the rim notes to be loose and raspy. On many pans, this causes a buzzing sound when playing the rim notes. Further, the use of seaming compound, an adhesive filler material placed between the head and sidewall prior to crimping, adds to these problems. When the pan is annealed (i.e., heat treated) the compound tends to melt and flow, leaving metal to metal junctions inside the crimped rim causing additional buzzing and looseness. These problems are exacerbated each time the instrument is retuned and are difficult to eliminate without negatively affecting other sound characteristics. This commonly recognized, but until now, unresolved problem results directly from use of starting material designed to be an industrial container, rather than a musical instrument.
A further disadvantage prevalent in traditional pans is that the shaping of the material within the pan has generally been achieved by approximation and eye-balling, without an appreciation for and/or precise application of the physics and geometry required to produce consistent pans of high acoustic clarity and optimal harmonic and timbre characteristics. Lack of precise bowl shape, note shape, and insufficient interstitial geometry all decrease the dynamic range, clarity, and stability of the instrument, and necessitate frequent and expensive retuning.
Mass Production Problems
Presently, production time for creating pans from industrial barrels remains dependent on the skill of the craftsman. There exists a lack of reproducibility from start to finish in the production of pans globally. The quality of the instrument has been substandard in comparison to other musical instruments. The cost for hand crafting has also caused the prices of pans to exceed what most consumers including schools, individuals, and professionals, can afford. Previous attempts to mechanize the process have not been successful from an economic, efficiency, or quality standpoint. Using an existing hand crafted pan as a model will only produce the same problems and poor quality, albeit on a larger scale.
For example, U.S. Pat. No. 6,212,772 discloses recent attempts to mechanize the production process using hydro forming. This process yields non-tunable, essentially unusable pans. The male mold was modeled after an existing hand crafted model. During hydro forming, the disc is formed over the male punch, not stretched into shape as during the pressing/stamping process of the present invention. This lack of stretching and tensioning yields a pan that is virtually un-tunable.
The art, therefore, is in need of improved processes for producing pans of higher quality and in a reproducible fashion.